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Yesterday I saw the following antenna:

Antenna picture

I am very puzzled, at first glance it seems a simple dish but:

  1. The mesh is really wide (low frequency?).
  2. It is pointing to Zenith. I think that most dish antennas rest in zenith position to offer less resistance to the wind. However, in that case it seems that the antenna can be moved just in AZ, and not in EL. What do you track pointing to the zenith?
  3. It has no feeder? There is a small box that I was unable to figure out what exactly was, but definitely it was not a usual feeder.
  4. Cables obstructing the aperture? Just take a close look and you will see how there are lines between the antenna focal point and the branch ends. (Although they could be non-conductive material, I was not able to distinguish them from that distance).
  5. Last but not least, taking a closer look to the image I noticed that the antenna was not a dish! Please, see how the part pointing towards 2 o'clock is not meshed and thus, the antenna is neither a dish!

I did an extensive Google search and asked friends but no one had seen an antenna like this before. Any of you has a clue?

Thanks!

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    $\begingroup$ As already answered, it is a hex beam. It is a compromise "beam" antenna whose main lobe is wider than a full sized beam antenna. I own a Traffie Hex-Beam and I found its ~5 dBi gain to be a nice advantage over a Dipole antenna. The advantage of course is smaller size -- my hex beam has a 9.5 foot rotation radius compared to 18 to 24 feet (or so) for full sized beams. Also, an ordinary TV style antenna rotator works great with this light antenna. I could hold it up by the main shaft with one-hand -- it only weighs 19 lbs. $\endgroup$
    – K7PEH
    Nov 6, 2016 at 22:04
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    $\begingroup$ Oh, one more advantage. Despite as shown in the photo, it does not require a heavy duty tower. I have mine mounted on the roof of our house on a 15 foot mast. That places the base of the hex beam antenna at about 40 feet. $\endgroup$
    – K7PEH
    Nov 6, 2016 at 22:07

2 Answers 2

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This is a “hex beam” antenna, a multi-band HF directional antenna. It is aimed in the direction you called “2 o'clock” in the photo.

The radial members are structural support and the wires looped around are the antenna elements; the loops of different sizes at different heights are elements for different bands.

The feed point is on the central mast, connected to the driven elements which are on the side which is "not meshed" and the wires instead go from the center to the perimeter.

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This is a multi-band directional antenna called a hex beam. It is not a dish, but each layer of wires is a different band directed towards the portion of the hex that is missing.

It is a relatively compact antenna and considered easier to assemble compared to other options allowing it to be mounted on smaller towers and give similar performance.

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